GAO finds electricity suppliers have addressed electromagnetic risks, agree that more research is needed
Recent Government Accountability Office (GAO) research found that most U.S. and Canadian electricity suppliers have assessed their systems’ vulnerability severe geomagnetic disturbances (GMD) resulting from solar storms, but have identified less information about the potential impacts of a high-altitude electromagnetic pulse (HEMP) caused by the detonation of a nuclear device.
A recent study found that GMD could cause voltage instability resulting in power system collapse and blackouts and damage to system components. In response, the North American Electric Reliability Corporation (NERC) recently created two regulatory standards that require certain U.S. and Canadian suppliers to assess their vulnerability to GMD and take steps to respond as needed. GAO was asked to review electricity industry actions to prepare for and mitigate electromagnetic risks.
The suppliers also agreed that more research is needed on both GMD and HEMP. All but two of the 13 electricity suppliers GAO contacted had assessed vulnerability to solar storms. Six of these 11 reported that they expected that impacts would be relatively minor.
Of the 11 suppliers that responded to GAO regarding HEMP, three said they had studied the impact of HEMP on their networks and two had integrated or planned to integrate HEMP-resistant features into control centers.
Of the 13 suppliers, 10 reported making technological and operational improvements, such as replacing older transformers and unprotected control centers, to improve overall network reliability that also provided some protection against GMD and HEMP risks.
Some of the U.S. suppliers indicated that the costs they had incurred to protect against GMD and HEMP have so far been relatively small and that they expect to recover those costs through customer rates.
As of May 2017, all 13 suppliers said they had complied with the NERC GMD regulatory standard. The second regulatory standard, which will require suppliers to further assess their vulnerability to GMD will be implemented in phases through 2022.
